The GISTM data format from Ilorin, Nigeria
The files are monthly files.
FileName is of the form 'ilrnmmyyyy' where 'ilrn' is the station code, 'mm' is the month of the year
and 'yyyy' is the year.
Column data type
[1] - Time in UTC
[2] - PRN
[3] - Az
[4] - elevation
[5] - CNo.
[6] - Lock time
[7] - S4 @ L1
[8] - DOY